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Bresser First Light Instruction Manual page 8

Refracting telescope

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This should then also be visible in the center of the field of view of the eyepi-
ece (f=20 mm). Polar alignment has been achieved. This setup requires some
patience, but rewards you with a good positioning option when searching with
celestial coordinates.
In this polar alignment, the graduated circles (scales) of the declination axis
(Fig 28) should be at "9" (= 90°) and the right ascension axis (Fig 29) at "0" (= 0
hours). If necessary, carefully rotate both scales to the appropriate values (alig-
ned with the arrows in each case).
Thus set, you can use the finding of celestial objects with the help of the gradua-
ted circles (scales) (see also 3.1. Possible objects of observation).
6. Fine alignment by means of LED viewfinder
Your telescope is now roughly aligned and adjusted.
To achieve a comfortable observation position, carefully loosen the screws of the
tube holder (Fig 9, X) so that you can rotate the telescope tube. Move the eyepie-
ce and LED viewfinder to a position from which you can observe comfortably.
The fine alignment is done by using the finder scope. Look through the viewfin-
der and try to align the polar star (Fig 26) with the illuminated point (Fig 14). The
shaft (Fig15, K) of the hour axis (Fig15, b), as well as the shaft (Fig15, E) of the
declination axis (Fig15, a) will help you with the exact setting.
7. First observations
Remove the caps from the openings for observation.
After you have adjusted the polar star in the LED viewfinder, you will be able to
see the polar star in the telescope when you now look through the eyepiece.
If necessary, you can now align the star more precisely with the aid of the
flexible shafts and adjust the focus using the focus wheel (7).
Furthermore, you can now set a higher magnification by changing the eyepiece
(smaller focal length). Please note that the magnification of the stars is hardly or
not at all perceptible.
TIP:
Eyepieces are lens systems that face the eye. With the eyepiece,
i
the image formed at the focal point of the telescope lens is recor-
ded, i.e. made visible, and magnified again. You need eyepieces
with different focal lengths to achieve different magnifications.
Start each observation with a low magnification eyepiece (= higher
focal length of 25mm).
8. Star search
At first, you will certainly find it difficult to orientate yourself in the starry sky, as
stars and constellations are always in motion and change their position in the
sky depending on the season, date and time.
The exception is the polar star. Through it runs the extended imaginary polar
axis of the earth. It is a fixed star and the starting point of all star charts. On the
drawing you can see some well-known constellations and star arrangements that
are visible all year round. However, the arrangement of the stars depends on the
date and time.
If you point your telescope at one of these stars, you will notice that it disap-
pears from the field of view of your eyepiece after a short time. To compensate
for this effect, operate the flexible shaft (Fig15, K) of the right ascension axis and
your telescope will follow the apparent trajectory of this star.
9. Setting circles
Stars and other heavenly bodies are positioned in the heavens by coordinates. A
star's place in the universe is determined by its right ascension and declination.
Declination (Fig 22, C) is the distance of a star from the celestial equator (Fig
25, d), measured in angular degrees. For stars north of the celestial equator,
the degree becomes positive. If the star is south of the equator, the degree is
marked with a minus sign.
Right ascension (Fig 22, J) is a distance of a star from the vernal equinox measured
on the celestial equator. The vernal equinox is the point of intersection of the
celestial equator with the apparent orbit of the sun (the so called Ecliptic) (Fig 25,
e). This happens in spring at the equinox (end of March). The value is counted in
time from 0 to 24 o'clock, contrary to the daily celestial revolution.
You can find more detailed information in star charts or the relevant specialist
literature.
10. Accessories
Several accessories (Fig 2) are supplied with your telescope as standard.
Important: When fitting accessories, ensure that the small clamping screws (Fig
12, X) for fixing are always hand-tightened.
10.1. Eyepieces
By changing the eyepieces, you determine the respective magnification of your
telescope.
Calculation of the magnification:
Focal length (telescope) ÷ Focal length (eyepiece) = Magnification
Examples:
Telescope's
Eyepiece's
focal length
focal length
1000 mm
25 mm
1000 mm
10 mm
10.2. Upright Prism
The upright prism produces an upright and laterally correct field of view and is
therefore particularly suitable for earth observation. But it is also very helpful for
easier orientation in the starry sky.
10.3. Barlow Lenses
With a 3x Barlow lens, you can achieve an additional increase in magnification
of 3x.
If necessary, the Barlow lens (Fig 23, 20) is inserted between the upright prism
(Fig 23, 19) and the eyepiece (Fig 23, 18).
10.4. Adaptor:
With the T2 adaptor you create the basis for the attachment of a photo camera
with T2 connection (lens connection).
To use the T2 adapter, first unscrew the retaining ring from the eyepiece tube
(Fig 21, 6). Then screw on the T2 adapter (Fig 21, 21) in its place.
In order to mount a photo camera, an additional camera-specific T2 ring is requi-
red, which is screwed between the camera and the T2 adapter.
10.5. Smartphone Adaptor
Insert the eyepiece into the smartphone holder and tighten the screw (Fig 24,
X) on the holder firmly. Then insert the smartphone holder with the eyepiece
into the eyepiece socket (6) or the upright prism (19) (refracting telescopes) and
hand-tighten the clamping screws (Fig 24, Y) on the socket or upright prism.
Now launch the camera app from your smartphone. Now press your smartphone
onto the holding plate and make sure it is properly attached. The camera must
be positioned exactly above the eyepiece. Centre the smartphone exactly over
the eyepiece so that the image is exactly centred on your display. It may be
necessary to use the zoom function to fill the image on the display. The suction
cups must be dry, clean and free from all types of dust and dirt. We do not take
responsibility for dropped and broken smartphones due to incorrect operation.
11. Dismantling
After a hopefully interesting and successful observation it is recommended to
store the entire telescope in a dry and well ventilated room. Some telescope
models allow you to separate the mount and tripod by simply unscrewing them.
In this case, your settings on the mount are retained. Do not forget to put the
dust-protection-caps on to the OTA opening and on to the eyepiece connection.
Also, you should stow all the eyepieces and optical accessories into their corres-
ponding containers.
12. Cleaning & Storage
Clean the lenses (eyepieces and/or objective lenses) only with a soft and lint-free
cloth (e.g. microfibre cloth). To avoid scratching the lenses, use only gentle pres-
sure with the cleaning cloth.
To remove more stubborn dirt, moisten the cleaning cloth with an eyeglass-
cleaning solution and wipe the lenses gently.
Protect the device from dust and moisture! After use, particularly in high humi-
dity, let the device acclimatise at room temperature for a short period of time, so
that the residual moisture can dissipate.
- 8 -
Magnification
Magnification
with 3x Barlow lens
40X
120X)
100X
300X

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